System for breaking a semiconductor wafer or other workpiece along a scribe line

Abstract

Apparatus and method for breaking a scribed semiconductor wafer utilizes two vacuum chucks, at least one of the vacuum chucks pivotable about a pivot line. The scribe line is aligned with the pivot line and relative movement between the vacuum chucks causes bending forces to be applied to the wafer and breakage of the wafer along the scribe line.

1. Apparatus for breaking a scribed semiconductor wafer or other scribed workpiece having a top workpiece surface and a planar bottom workpiece surface along a scribe line formed in the top workpiece surface without engaging the top workpiece surface with structure of the apparatus applying external compressive forces to said workpiece and for separating said workpiece into a first workpiece portion having a first workpiece portion top surface and a planar first workpiece portion bottom surface and a second workpiece portion having a second workpiece portion top surface and a planar second workpiece portion bottom surface along said scribe line, said apparatus comprising, in combination:
 a first vacuum chuck having a planar, upwardly directed first workpiece support surface for positively supporting said first workpiece portion over substantially the entire area of said planar first workpiece portion bottom surface, with the planar first workpiece portion bottom surface facing said planar, upwardly directed first workpiece support surface, and said first vacuum chuck applying a vacuum at the planar first workpiece portion bottom surface to maintain said first workpiece portion connected thereto and immovable relative thereto; 
 a second vacuum chuck adjacent to and pivotally connected to said first vacuum chuck and having a planar, upwardly directed second workpiece support surface for positively supporting said second workpiece portion over substantially the entire area of said planar second workpiece portion bottom surface, with the planar second workpiece bottom surface facing said planar, upwardly directed second workpiece support surface, and said second vacuum chuck applying a vacuum at the planar second workpiece portion bottom surface to maintain said second workpiece portion connected thereto, said first and second vacuum chucks including facing side walls having straight top edges meeting along a straight pivot line; and 
 vacuum chuck mover structure for causing pivotal movement of one of said first and second vacuum chucks downwardly relative to the other of said first and second vacuum chucks about said pivot line while the straight top edges meet to exert bending forces on the workpiece supported thereby while said first workpiece portion remains positively supported by and connected to said first workpiece support surface due to application of vacuum by said first vacuum chuck without engaging the first workpiece portion with structure of the apparatus applying external compressive forces to said first workpiece portion top surface and while said second workpiece portion remains positively supported by and connected to said second workpiece support surface due to application of vacuum by said second vacuum chuck without engaging the second workpiece portion with structure of the apparatus applying external compressive forces to said second workpiece portion top surface to break the workpiece along the scribe line formed therein, said first and second workpiece support surfaces and said pivot line lying in a common plane prior to said pivotal movement of one of said first and second vacuum chucks to exert bending forces on the workpiece, and said pivot line disposed adjacent to and in alignment with said scribe line. 
 
     
     
       2. The apparatus according to  claim 1  wherein said vacuum chuck mover structure is connected to said second vacuum chuck to pivot said second vacuum chuck about said pivot line while said first vacuum chuck is immobile. 
     
     
       3. The apparatus according to  claim 2  wherein said vacuum chuck mover structure includes a motor and linkage interconnecting said motor and said second vacuum chuck. 
     
     
       4. The apparatus according to  claim 1  wherein said facing side walls extend downwardly from said pivot line, said facing side walls diverging from one another in a downward direction when said first workpiece support surface and said second workpiece support surface are co-planar. 
     
     
       5. The apparatus according to  claim 4  wherein the facing side wall of said second vacuum chuck defines an acute angle with said second workpiece support surface. 
     
     
       6. The apparatus according to  claim 4  wherein each of said first and second vacuum chucks includes a chuck plate forming one of said facing side walls defining a cavity closely adjacent to the facing side wall thereof and extending downwardly from the workpiece support surface thereof and a porous member in said cavity for placement in communication with a vacuum source and for applying a vacuum to the bottom of said workpiece. 
     
     
       7. The apparatus according to  claim 6  wherein said porous member is formed of porous ceramic material and has an upper porous member surface comprising a portion of a workpiece support surface. 
     
     
       8. The apparatus according to  claim 1  wherein said first workpiece support surface and said second workpiece support surface define an obtuse angle while said first vacuum chuck and said second vacuum chuck exert bending forces on said workpiece. 
     
     
       9. The apparatus according to  claim 1  additionally comprising workpiece transport structure for selectively transporting the workpiece relative to said first vacuum chuck and said second vacuum chuck. 
     
     
       10. The apparatus according to  claim 9  wherein said workpiece transport structure includes a mounting frame employed to position the workpiece over the first vacuum chuck and over the second vacuum chuck, mounting frame moving structure for selectively moving said mounting frame and a support sheet stretched across said mounting frame, said workpiece disposed on and secured to said support sheet. 
     
     
       11. The apparatus according to  claim 10  wherein said mounting frame moving structure includes at least one frame movement stage for selectively rotating said mounting frame and for selectively linearly moving said mounting frame. 
     
     
       12. The apparatus according to  claim 10  wherein said mounting frame moving structure includes a plurality of frame movement stages, each of said frame movement stages including a linear motor, the linear motors of each frame movement stage being independently operable. 
     
     
       13. The apparatus according to  claim 1  additionally comprising a scribe line alignment stage for scanning the workpiece to check alignment of the scribe line.